Tool holder



Patented Aug. 29, 1922.

2 SHEETS-SHEET Z- ZQ-Mar'iizvv TRETVILLIE O. MARTIN, OF JACKSON, TENNESSEE.

r001; HOLDER.

i ifZWAAlSE;

Application filed November 30,1920, Serial Nor-4273381." Renewed Nay 12, 1922. -Seria1 No; 560,447."

1' 0 all ii /1 om it 02mg concern Be it known that l, llanvimiin O, ldnnrin, a citizen ot the llnited States, residing at Jackson, in the: eouutyof Madison and State of Tennessee, have invented certain new and,

useful Improvements in Too Holders, of which the rollowingis a specil'ication.

This invention relates to machine tool holders and has as one 0t its: objects to provide tool holder adapted toreceive and firinlysupport a tool or tool bitv o l-any ordinary length. andnwhich maybe of diinensions and cross sectional shape tolit within the holder, so that worn or broken drill bits may be employed in. thestead oi the more expensive toolbits and thus be made to-serve a usci'ul purpose alter they have become un-,

o1"? resiliency and whereby one of the jawv members in particular will be so joined with the shank of the holder as to increase the resiliency of the connection and adapt the said jaw member tobe morereadily and etfectually clamped against the tool and with-.

out likelihood of breakage of .the connection.

in the accompanying drawings:

Figure l is a side elevation of one form oi tool holder embodying the invention;

Figure 2 isa vertical longitudiinil sec tioual view theretlnrough;

Figure 3 is a perspective view of the forward end or nose oi' the holder;

Figure 4t is a vertical. transverse sectional View on the line l+i of Figure 1;

Figure 5 is a similar view illustrating a slight modification or the invention;

Figure 6 is a side elevation of a modified formof holder;

Figure 7 is a vertical longitudinal sectional view through the holder shown in Figure 6;

Figure 8 is a top plan view of the holder shown in Figures 6 and 7 Figure 9 is a vertical transverse sectional view on the line 9 9 of Figure 7'.

In that form of the invention shown in Figures 1 to 5 inclusive, the tool holder is Specification of Letters Patent.

is formed with a tool-receiving cheated by the numeral 3 and in the nature or abore extending longitudinally from end designed to supportand clamp a bit which is oi round or polygonal contour in cross section. whereas the holder illustrated in Figures-ll to 9 inclusive is designed to supportand clamp a pair of tools andis to be employed more especially in cutting off packing rings and in performing similar operations. lint-he form of theinvention illustrated inFigur-es 1 to 5 inclusive, the shank of the holder is indicated in generalby the nu-' moral. l and thisshank isprovided atits outerend with a nose-2 which will presently be morespecifically referred to. The shank the specific i'orm otrtool orbit. to be held and inthe tirstltourfigures of the drawings is cylindrical andin Figure 5 is reetangular i the tool or. hit at, inthe former: instance be mg circular in crossseetion andithetoolor bit 5 in the lattervinstancebeing rectangular lnasmuchias the socket or in. cross section.

socket inbore opens through the opposite ends of the shank, it will be evident that a tool or tool bit shorter or longer than the shanlcas a whole .ma be gripped and held withequal faeilitfyl The shank at its forward or outer portion is dlvidedbyslotstl formed in the i opposite side walls otihe bore or socket 3, so as to provide upper and lower jaw men1 bers 7 and 8 respectively; The slots 6 do not extend parallel to the axis of thesoeket or bore 3, but obliquely to the said axis the. forward ends oil' the slots being. located sul stantially at opposite sides of the axis of the bore, but the slots rearwardly of their said ends being inclined downwardly with relation tothe axis and terminating at-their rear or innerendsnin substantially cyiindrical enlarged por ions 9, the lower sides of the walls of which are substantially flush with the bottom of the socket or here 8, as best shown in Figure 2 of the drawings. Thus the tool shank is of substantially uniform thickness in a vertical direction at the line of juncture of the lower jaw 8 with the rear portion of the shank, and by inclinin the slots 6 in the manner stated with relation to the axis of the bore or Socket 3, the lower side of the enlarged portions 9 ot the slots are located relatively close to the under side of the shank. Thus the jaw S is given increased resiliency at its point of juncture with the shank of the holder and may be urged in the direction of the jaw 7, to clamp the tool to be held, without likelihood of the jaw 8 being broken off and also without likelihood of the shank, rearwardly of the inner ends of the slots 6, being split. The manner in which this increased resiliency is obtained will be evident when it is considered that the holder at the point of juncture of the upper jaw 7 with the rear portion of the shank is not of uniform thickness in a vertical direction because the upper sides oi the enlarged portions 9 of the slot-s 6 are located considerably below the upper side of the socket or bore 3. Therefore when the holder is disposed within the usual tool post and is clamped by pressure exerted against the edges of its upper and lower jaw members, the lower jaw member 8 will be sprung in the direction of the upper jaw member but as this connection with the rear portion of the shank is resilient to a relatively high degree, there will be no likelihood of the connection being fractured, and also it may be caused to more firmly and securely grip the tool or tool bit disposed within the bore or socket 3. As stated the forward or outer end of the bore or socket 3 opens at the upper side of the nose 2 so that the upper side of the said nose constitutes a continuation of the lower portion of the wall of the said bore or socket and thus the working end of a tool or tool bit disposed within the bore or socket will be given firm support upon the nose.

In that form of the invention shown in Figures 6 to 9 inclusive, the shank of the holder is indicated by the numeral 10 and is formed with a transverse slot 11 extending longitudinally but non-parallel to its axis and in tact inclined in the same manner as the slot 6 in the first described form of the invention. In this latter form of the invention the opposite side faces of the shank or body of the holder are formed with recesses 12 having beveled upper and lower walls 13 and adapted to receive a pair of tools or tool bits H- which are of blade-like form and have beveled upper and lower edges 15 for engagement by the beveled walls 13 of the recesses. It will also be observed by reference to Figures 6 to 9 that the slot 11 is provided at its inner end with a cylindrical enlarged portion 16 the lower side of the wall of which is located immediately opposite and substantially in a plane with the bottom walls of the recesses 12 so that in this latter form of the invention as in the first-described "form, the holder at the point of juncture of the lower jaw with the rear portion ot the shank is of uniform thickness in a vertical direction.

Having thus described the invention, what is claimed as new is:

1. A tool holder comprising a shank provided with a tool-receiving socket extending from end to end thereof with its axis inclined with relation to the planes of the upper and under faces of the shank, the said shank being formed with a transverse longitudinally extending slot opening through the opposite walls of the socket. the said slot extending non-parallel to the axis of the socket with its inner end located substantially in the plane oil. the bottom wall of the socket.

2. In a tool holder of the class described, a shank comprising a solid body provided with a tOOLlQCQlVlTlf socket extending from end to end thereof, the said shank being termed with a slot in the wall of its socket extending longitudinally thereof for the major portion oi? the length of the shank whereby to provide upper and lower tool gripping jaw portions, the said slot at its outer end terminating substantially in the plane of the median line of the socket and therefore substantially medially dividing the socket to adapt the jaws at their outer ends to bear against substantially equal areas of: the tool to be held, the slot being inclined from its said outer end obliquely with relation to the median line of the socket and at its inner end being formed with an enlargement the lower side of which is located substantially in the plane oil the lower side of the socket whereby the body at the juncture of the lower jaw therewith is oi unil'orm thickness throughout its width and rendered resiliently yieldable to readilv adapt the lower jaw to be sprung in the direction of the upper jaw and into clamping engagement with the tool to be held when the holder is clamped in a tool post.

In testimony whereof I aflix my signature, TREVILLIE O. MARTIN. in. s] 

